Differential expression and intrachromosomal evolution of the sghC1q genes in zebrafish (Danio rerio)

The secreted globular head C1q (sghC1q) genes can be characterized as a family of genetic loci encoding signal peptides followed by single complement component 1q globular (gC1q) motifs. Members of this family have been referred to as precerebellin-like (Cblnl), C1q-like or ovary specific C1q-like factors, and are transcribed in response to infection and/or during early development. This study was primarily undertaken to identify the zebrafish sghC1q (or DrsghC1q) genes that increase their transcription in response to infection and to examine their transcriptional patterns during early development. Twenty sghC1q genes were found in the zebrafish (Danio rerio) genome (Zv9). Two of the examined twenty genes showed significant up-regulation within 24 h of infection with the fish pathogen Streptococcus iniae, and eleven of the examined twenty were expressed during early development. Due to the clustered nature of these genes on chromosomes two and seven, intrachromosomal duplication events are hypothesized and explored.

Graphical abstractPhylogeny, chromosomal characteristics and expression of the twenty zebrafish (Danio rerio) secreted globular head C1q (DrsghC1q) genes.Figure optionsDownload full-size imageDownload high-quality image (145 K)Download as PowerPoint slideHighlights► Twenty sghC1q genes were found in the zebrafish genome. ► Intrachromosomal duplication events likely created these genes. ► Transcription during early development and inflammation were examined. ► Two genes were expressed at 24 h post infection. ► Eleven other genes were expressed during early development.